i also have the same problem as you. and i think the dev has no intention to fix this. i have post the problem months ago. but there is no fix!!...
you can't change size, color, position if you use PGS (bluray) Subtitle
i found out that all of my bluray subtitle (MKV) appear a little higher (and smaller) than my old 1186 player here is the pics 1186 player...
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